Green - Sleep Flashcards
Emotionally-triggered, transient muscle weakness
Cataplexy
Graph that represents the stages of sleep as a function of time
Hypnogram
High amplitude brain waveform observed by EEG during stage 2 of NREM sleep
K-complex
Neurohormone secreted by the pineal gland that modulates the sleep-wake cycle
Melatonin
Sleep stages 1-3
NREM sleep
Neuropeptide secreted by the posterior lateral hypothalamus that promotes waking. Also called hypocretin
Orexin
Rapid eye movement sleep
REM Sleep
Direct entry into REM sleep after REM sleep deprivation
REM rebound
Found in anterior hypothalamus; controls the circadian rhythm
Suprachiasmatac nucleus
Time of maximum sleep drive and minimal arousal
Sleep gate
Burst of lower amplitude brainwave activity observed by EEG during stage 2 of NREM sleep
Sleep spindle
Stage 3 sleep
Slow wave sleep
Part of lateral hypothalamic region; active during wakefulness; secretes histamine
Tuberomammillary nucleus
Part of hypothalamus; secretes GABA: active during sleep
Ventrolateral preoptic nucleus
Possible reasons for sleep
. energy conservation and replenishment 2. tissue restoration 3. boosting of immune system function 4. consolidation of learning and memory 5. renormalization of synaptic strength and number
Lack of sleep can cause:
Increased appetite
Impaired memory
Reduced cognitive abilities
Mood swings
Hallucinations
Death
Synthesis of melatonin, by the pineal gland, increases as ?
Light decreases
When you are awake, what is shown on eeg?
High frequency, low amplitude EEG waves - beta waves
Stage 1 sleep consists of a drowsy period. What is seen on EEG?
Slightly lower frequency and higher amplitude of EEG waves
- theta waves
Stage 3 sleep on EEG?
Low frequency and high amplitude EEG waves - delta waves
Physiological changes seen in NREM sleep
Decrease in: blood pressure, heart rate, muscle tone, breathing rate, metabolic rate, body temperature, body movements (although tossing and turning may occur)
Also see sleepwalking and sleep talking in this stage
EEG readings in REM sleep
Activity that is similar to awake state
Penile erection occurs during
REM sleep
Physical changes that associate REM sleep?
Increase in blood pressure, heart rate, metabolic rate.
Penile erection
When stimulated, causes awakening of sleeping animal
RAS
When stimulated, causes awake animal to fall asleep
Thalamus
Nonadrenergic neurons of locus coeruleus and serotonergic neurons of raphe nucle are active during
Wakefulness
Neurons from the hypothalamus synthesize ____ which promotes waking
Orexin/ hypocretin
This nucleus’s neurons help to induce sleep by inhibiting networks responsible for awake state.
Uses GABA and galanin as inhibitory neurotransmitters
Ventrolateral preoptic nucleus of hypothalamus
Neurons in reticular activating system, locus coeruleus and raphe nuclei active
Orexin synthesize neurons active, which reinforces.
Awake state
VLPO neurons active, which inhibit neurons responsible for wakefulness
Orexin - synthesizing neurons inhibited
Sleep state
Adenosine builds up; VLPO sends signal to arousal centers to stope producing neurotransmitters that keep us alert
Falling asleep
SCN generates cue that signals VLPO to stop firing. Arousal centers activated
Waking up
The inability to sleep for a sufficient length of time
Insomnia
Causes of insomnia
Stress, jet lag, caffeine, depression, medication, anxiety
How does caffeine work to stop sleepfulness?
By blocking the effects of adenosine
Interupted breathing due to obstruction of upper respiratry tract, causing interruptions in the sleep of people
Obstructive sleep apnea
What can be the outcomes of people with chronic, untreated obstructive sleep apnea?
Chronically tired during daytime
Development HTN, increased risk for MI, CVA
____ % of people with obstructive sleep apnea are not obese
30
What causes breathing levels to increase in obstructive sleep apnea
Decreased SAO2, increased CO2
Efferent signal to diaphragm not sufficient to signal breathing. Occurs in all sleep stages, but more common in early NREM
5% of all apneas.
Central apnea
Cause not completely understood.
Could be from improper development of respiratory drives which causes pt to be unable to awake themselves from slow wave sleep in the event of apnea
SIDS
What can help infant arousal from SWS, in preventiono of SIDS
Having the infant on their backs
At night, patient will have a searing, prickling, or crawling sensation in their legs which is improved with a cyclic, rhythmical movements of legs, even during sleep.
Common in older adults / elderly
Restless leg syndrome
- excessive daytime sleepiness 2. may have frequent periods of REM sleep without going through NREM sleep 3. lose muscle control (cataplexy) during episodes of emotion
- symptoms also include hallucinations during onset of both sleep and wakefulness,
sleep paralysis, automatic behavior, and disrupted nighttime sleep
5. abnormal boundaries of wakefulness, NREM sleep, and REM sleep 6. either REM sleep inappropriately generated or inhibition of REM sleep impaired - patients have lost orexin/hypocretin-synthesizing neurons
Narcolepsy
symptoms also include hallucinations during onset of both sleep and wakefulness,
sleep paralysis, automatic behavior, and disrupted nighttime sleep
lost orexin/hypocretin-synthesizing neurons
Excessive daytime sleepiness
Cataplexy
Narcolepsy
Brainstem disorder which prevents the paralysis of muscles. Characterized by kicking, punching, or otherwise acting out aggressive dreams during sleep.
Mostly in men over age 50
Associated with an increase incidence of Parkinson’s disease
REM sleep behaviour disorder (RBD)
Lack of sleep associated with increased incidence of?
Obesity, diabetes, CVD
